A 19th-century subterranean reservoir repurposed as a contemporary art cave.

The hidden "ballroom" under a mansion lake was built by a criminal who ate a cyanide pill during his trial.

A cabin completely covered in coffee mugs, where visitors are welcome to leave one of their own—if they can find an empty nail.

This jaw-dropping 19th-century bridge uses its reflection to form what appears to be a perfect circle.

An abandoned cemetery lies in ruins as the surrounding forest swallows it whole.

A stone arch leads to a cavernous 1930s spring house tucked away in the Pennsylvania woods.

This eye-popping Icelandic crater lake is surrounded by red volcanic rock.

A collection of old steam and diesel locomotives sitting in a fenced-off garden.

One of the dwarven trees dates back to 1625 and survived the Hiroshima bombing.

In northeastern Poland, the ruins of a massive granary overlook the Narew River.

A unique museum dedicated to culture and artistry of carpet weaving.

Twin Peaks' real life Double R Diner has been restored to its damn fine television look.

For those going through a life transition, a place to leave behind a piece of your former self.

The sound of swaying stalks in this stunning grove has been named a governmentally recognized sound.

The futuristic test model of an iconoclastic visionary who wanted to redesign the world.

This supper-club-turned-concert-venue still serves drinks at its original rotating bar.

World's oldest and largest space launch facility, once a secret missile testing site.

Unexplained bald patches in the landscape grow and recede over time, as though they are somehow alive.

This floating garden in the sky is straight out of a fairy tale, but the real thing is nothing short of magical.

This huge metal monument is slowly being stripped to its concrete skeleton.

This unique temple complex remains off the typical tourist trail.

This whimsical fountain pays tribute to Toronto's four-legged friends.

A collision of human error and natural geothermal pressure created this rainbow-colored geologic wonder.

This neon landmark has been posing this deadpan question to follicly-challenged Dubliners for over 50 years.